Dublin Institute for Advanced Studies

Global and Local Seismology

This research area investigates the structure and dynamics of the deep Earth, from its crust to its core. Seismic waves generated by distant global earthquakes, are used to study wave propagation by applying tomographic methods that are similar to medical imaging techniques. These yield information about the chemical and thermal state of the Earths crust and mantle and the tectonic processes that operate deep within the Earth that are responsible for the growth and deformation of continents and oceans. In addition to global-scale seismic imaging investigations of the Irish and European lithosphere using locally deployed seismic instruments are also undertaken. A permanent array of seismic instruments is also deployed across Ireland to monitor seismic activity on land and the surrounding offshore. One particular focus of this global research theme is the North Atlantic lithosphere between western Europe and eastern North America. This is strongly related to and complimentary to the Marine Geophysics research theme.

GLOBAL TOMOGRAPHY

Seismic stations around the world record the tiny vibrations of the Earth’s surface caused by earthquakes thousands of kilometers away. Recordings of these vibrations (seismograms) enable seismologists to perform seismic tomography, or 3D imaging of the Earth’s deep interior. This image below shows variations of seismic velocities at a 100-km depth in the Earth’s mantle. High velocities indicate low temperatures, most noticeable within the cold, thick tectonic plates of the ancient cores of continents (cratons). Low velocities indicate high temperatures or partial melting of the rock, such us beneath the mid-ocean ridges where new oceanic crust is formed.

Some recent research by DIAS Geophysics scientists, with major impact internationally:

Ireland Array is a new array of broadband seismic stations deployed across Ireland by DIAS Geophysics The backbone component of the array is formed by 20 stations, equipped with Trillium 120PA seismometers and distributed uniformly across Ireland. These 20 stations have been installed in 2010 – 2012 and will be deployed for 5 years. Deployments of additional 15 stations (each with a Guralp 40T seismometer) are used to complement the backbone-component coverage and to target fine structure of the subsurface in specific target areas.

Ireland Array is a major new geophysical facility, producing abundant seismic data. It will reveal Ireland’s deep structure and evolution in unprecedented detail. Ireland Array will also underpin geothermal energy research by illuminating in detail the structure of Ireland’s crust and entire lithosphere. New insight into 3-D regional lithospheric structure and evolution will also benefit basin-evolution research, relevant for hydrocarbon exploration. Yet another target of Ireland Array will be Ireland’s seismicity, modest but insufficiently understood at present. Ireland Array invites collaborations with Earth scientists in Ireland, as well as abroad, and is aimed to benefit the entire community. For more details click here.

DIAS Geophysics are partners within the @eurovolc H2020 project where the first annual meeting occurred this week at the Volcano Observatory of the Azores Islands at the University of Azores in Ponta Delgada #eurovolc

With support from the @GeolSurvIE , €1.5m is being invested to expand and upgrade the Irish National Seismic Network (insn.ie) New funding will result in more stations, greater coverage & more accurate recording of earthquakes in Ireland. tinyurl.com/yb6ho2cp

Dr. Duygu Kiyan recently presented her work at the AGU Meeting in Washington, USA. Along with her colleagues, she is imaging Ireland's lithosphere using legacy and newly acquired magnetotelluric data across Ireland. @iCRAGcentre@DIAS_Dublin@GeolSurvIE@tcdastro

"Forecasting the Unpredictable: Earthquake science in a crowded world" by Prof. John McCloskey is DIAS's 2018 Statutory Public Lecture of the School of Cosmic Physics. Schrodinger Theatre, School of Physics, Trinity College Dublin, Wednesday Dec 12th at 18:30. Admission is free!

The field season of the DIAS led HERSK project started last week when Icelandic Met Office engineers transported seismic gear with skidoos onto Hekla volcano. The HEkla Real-time Seimic networK project
is funded by the GSI shortcall program and led by Martin Möllhoff at DIAS.

This inflation has critically stressed the rocks in the volcano, such that small local earthquakes are being triggered by the tiny ground shaking from large distant earthquakes in the surrounding Pacific ‘ring of fire’.

Geophysicists from DIAS have recently assisted the University of Edinburgh & the Instituto Geofisico at the Escuela Politecnica Nacional (IGEPN), deploy a network of seismometers at Sierra Negra, a large basaltic volcano in the Galapagos Islands, Ecuador.

#DIASDublin welcomed Mr. Yukiya Amano, DG of the International Atomic Energy Agency @iaeaorg today where, as a guest of the Department of Foreign Affairs and Trade, he gave a keynote address on "IAEA: Atoms for Peace and Development". Retweeted by
DIAS Geophysics